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I'm having trouble with my mechanics course. I'm having trouble figuring out what the question is asking me with all this polar coordinare stufff, and how to go about the question. Here are some of the questions.

1. A particle starts on the x axis at (b, 0) at time t = 0, and moves at constant speed v in a straight line in the +y direction. Derive explicit expressions (in terms of b, v, and t) for the polar coordinates r and f as functions of time, and for the time derivatives f fr&, &, &r&, and && . Finally, calculate the radial and azimuthal acceleration components ar and af.

My general approach is to wrtite the pythagorean therorem for distace after time t to get the radious, and then use trig to get an expression for the angle. But, then I don't really know what to do get the derivatives.

There are other questions but I'm not sure how to start them, and so don't have an attempted solution.

Thanks

Liam

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# Homework Help: Problems with mechanics

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